The objects are “relatively indistinct” but the larger of the two appears to be about 75 feet across, according to John Young, emergency response general manager for the Australian Maritime Safety Authority.

They were spotted in satellite imagery taken on Sunday about 1,400 miles off the coast of Perth.

Australian Prime Minister Tony Abbott said more analysis was needed before it could be determined whether the objects were from the missing Malaysia Airlines jet, but Young called the discovery “the best lead we have right now.”

“The task of locating these objects will be extremely difficult, and it may turn out that they may not be related,” Abbott said. However, he characterized the find as “new and credible information” in the search for the Beijing-bound plane, which disappeared March 8 after leaving Kuala Lumpur.